Claudia Lacy says she can accept anything : even that her youngest son committed suicide -- if it 's proven and explained to her .

However , she says , local and state investigators have done neither to support their theory that Lennon Lacy hanged himself one summer night .

`` That 's all I 've ever asked for : what is due , owed rightfully to me and my family -- justice . Prove to me what happened to my child , '' Lacy says .

She says she 's long lost confidence in the Bladenboro Police Department and the North Carolina State Bureau of Investigation .

Now , the FBI is looking into Lacy 's death and the local and state investigations that followed .

Without clear answers , the past few months without him have not been easy .

`` I look for him and I do n't see him . I listen for him and I do n't hear him , '' Lacy says .

The last time Lacy saw and heard her son was August 28 . Lennon , 17 , played the lineman position for the West Bladen High School Knights , and was focused on football .

His family says that night , he packed a gym bag , washed his ankle brace and hung it on the clothesline to dry before heading out for an evening walk .

The teen had asthma , his mother says , and a doctor had recommended he exercise outdoors at night when the temperature and humidity dropped . Around 10:30 , Lennon left his family 's small apartment and headed down a dirt road .

His family never saw him alive again .

Just before 7:30 the next morning , he was found hanging from the frame of a swing set in the center of a mobile home community . According to medical documents , his body was covered in fire ants .

Lennon 's mother was called to the scene several hours later , after he 'd been placed into a body bag .

`` It was unreal . It was like a dream . It was like I was not seeing what I was seeing , '' Lacy says .

Immediately , Lacy believed her son 's death was the result of some foul play .

`` He did n't do this to himself , '' Lacy says .

She believes Lennon was lynched .

`` He may have either been strangled somewhere else or been placed there or he was hung there while people were around watching him die , '' Lennon 's older brother , Pierre Lacey says .

However , North Carolina 's Chief Medical Examiner Dr. Deborah Radisch declared his death a suicide .

When a state investigator asked Lacy if her son had been depressed recently , she told them he had -- because a relative had died recently . The state medical examiner cited that exchange in the autopsy report . Lacy says she did not mean that her son had been suffering from depression .

`` When you just lose someone close to you , you 're going to be depressed , upset , in mourning , '' Lacy says .

The family says Lennon had not changed his routine and was focused on college and football -- and distracted by his girlfriend .

The teen had been dating a 31-year-old white neighbor . The age of consent in North Carolina is 16 . Some people in their small , southern town did not like that the two were together . Lacy did not like their drastic age difference .

`` I was shocked , disappointed . I also , initially told him how I felt - that I did not approve of it , '' Lacy says .

In the wake of his death , some wondered whether Lennon had been killed because he was in an interracial relationship .

A week after Lennon was buried , a local teenager was arrested for defacing his grave .

`` There are too many questions and it very well could be a lynching or a staged lynching . We do n't know -- but what we do know is there has to be a serious and full investigation of these matters , '' says Rev. William Barber , a national board member for the NAACP .

The NAACP hired Florida-based forensic pathologist Christena Roberts to analyze the case and Dr. Radisch 's autopsy , completed for the state .

Roberts ' first concern : basic physics . Lennon was 5-foot-9 . The crossbar of the swing set frame he was found hanging from was 7-foot-6 , according to the NAACP review . With no swings or anything at the scene on which he could have climbed , according to the review , it 's unclear how Lennon reached the top .

`` His size , his stature does not add up to him being capable of constructing all of this alone - in the dark , '' Lennon 's brother says .

According to the 911 recording and the initial police report , a 52-year-old woman got the 207-pound teen down , while she was on the phone with an emergency dispatcher .

`` Dr. Radisch also noted that she was not provided with photographs or dimensions of the swing set . Without this information , she would be unable to evaluate the ability to create this scenario , '' according to the NAACP review .

Lacy says she told investigators that the belts used to fashion the noose did not belong to Lennon .

`` I know every piece and every stitch of clothes this child has -- I buy them , I know . Those were not his belts , '' Lacy says .

The Bladen County Coroner and Medical Examiner Hubert Kinlaw believed the belts might have been dog leashes .

Radisch thought that `` some portion must be missing because there was no secondary cut in either belt . The cut would have been necessary to bring down Lennon 's body , '' according to the review .

Also , the shoes Lennon was wearing when his body was found were not his , according to his family .

Lennon 's brother says he left home that night wearing size 12 Air Jordan 's . However , he was found wearing size 10.5 Nike Air Force shoes . Those shoes were not with Lennon 's body when he arrived at the state medical examiner 's office , according to the NAACP review .

`` He 's going to walk a quarter mile from his house in a pair of shoes that 's two sizes too small after he takes off his new pair of shoes - and this is a 17-year-old black kid with a brand new pair of Jordan 's on . He 's going to take those Jordan 's off and just get rid of them and put on some shoes that 's not his -- we do n't know where he got them from , no laces in them -- and continue to walk down this dirt road late at night to a swing set in the middle of the trailer park and hang himself , '' Lacey says .

`` How can I believe that ? '' Lacey added .

There are also questions about who first declared Lennon 's death a suicide .

`` Dr. Radisch noted that her determination of -LRB- manner of death -RRB- in this case as suicide was based on the information she was provided by law enforcement and the local medical examiner . She would have likely called the -LRB- manner of death -RRB- ` pending ' while awaiting toxicology and investigation but the -LRB- local medical examiner -RRB- had already signed the -LRB- manner of death -RRB- as suicide , '' according to the NAACP review .

However , in the summary of the case , written the day Lennon was found , the local medical examiner asked `` did he hang self ? Will autopsy tell us ? '' Kinlaw also left the conclusion on the manner of death `` pending . ''

Local police and state investigators declined to speak with CNN . CNN asked to interview Radisch about the statements attributed to her in the NAACP review . Instead , a department spokesperson confirmed the exchanges through a written statement :

`` The comments that were released by the NAACP were a synopsis of a professional exchange between the NAACP 's independently-retained forensic pathologist and Dr. Radisch , '' according to a spokesperson for the North Carolina Department of Health and Human Services .

Lennon 's family believes there was a rush to judgment . And until someone clearly explains and proves how her son died , Lacy says she 'll keep fighting until she gets answers .

`` I take it one day at a time . That 's all I can say , '' Lacy says .

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FBI is looking into the death of Lennon Lacy , 17 , and the investigations that followed

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Lacy was found hanging from a tree after he went for a walk on a summer night

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His mother says he did not commit suicide